Patent GB-436610-A (GB)
Title: Improvements in or relating to web renewing mechanism for printing presses
IPC: B65H19/18
Filed: 1934-07-11
Abstract: 436,610. Feeding webs. TRIGGS, W. W., 57, Lincoln's Inn Fields, London.-(Wood Newspaper Machinery Corporation; 501, 5th Avenue, New York, U.S.A.) July 11, 1934, No. 20357. [Class 100 (i)] Web-renewing mechanism for web-printing machines comprises a movable support or reel adapted to carry two or more web rolls and means for rotating each web roll through its axis on the support in which a common drive, including a variable speed mechanism and friction clutch means, is provided for the rolls and the drive of each roll is selectively controlled by mechanical clutch means on the support. When a join is to be made a pivoted frame carrying a brush is lowered into proximity with the running web, the fresh roll is brought into rotation and then moved into position closely adjacent the running web, the brush is operated to press the web against the new roll, the old web is severed, the new roll is moved into running position, the brush frame is raised and a device at the delivery end of the press is caused to displace the products containing the doubled thickness of web. The running roll R, Fig. 1, and spare roll S are carried by a threearmed frame rotatable on a shaft 6 in a stand and driven by an electric motor 9 to bring the rolls successively into running position. Side register of the rolls and spider frame is effected by a motor 10 and normal running tension is applied to the active roll by belts 13, which carry adjustable weights 20. A frame 23, Figs. 1, 20, carrying a web pressing brush 21 and a severing knife 24 is pivoted upon a shaft 131 and is adapted to be lowered and raised by an electric motor which through gearing and crank mechanism operates arms loose upon the shaft 131 and connected to the frame 23 by safety shearing pins. During the lowering of the frame 23, the new roll S is set into rotation by the following means. Each roll spindle 12 is driven from a shaft 31, Fig. 4, through suitable gearing which remains engaged in spite of any slight sag of the roll shafts under the weight of the rolls and which includes a gear 43 concentric with the shaft 6 of the spider frame and a gear 44 secured to a clutch member 45 with which is adapted to engage a movable clutch member 58 slidably mounted on but splined to a sleeve fixed to the spindle shaft 48. The clutch member 58 is moved into and out of engagement by a yoke 61, Figs. 3 and 4, mounted on a rock shaft 65, which can be rotated by a spring 68 but is normally held with the clutch disengaged by a cam 73 on the spider frame which engages a roller 71 carried by the yoke 61. The cam 73 is cut away so that the clutch may engage between the points A, B but this engagement only takes place when a spring-controlled latch 63 carried by the yoke 61 is released by a fixed projection 77, this constituting a device which prevents the clutch teeth from engaging when the spider reel is run accidentally or otherwise in a clockwise direction. The shaft 31 is adapted to be driven from a variable speed device 101 through a magnetic clutch, the circuit of which includes a switch in a multiple switch driven by the motor which raises and lowers the frame 23 and a rheostat also driven by this motor, the rheostat causing a gradual increase of the voltage applied to the clutch as the frame 23 is lowered. The variable speed gear 101 is adjusted automaticaly in accordance with the diameter of the roll by means of a roller 119, Fig. 15, carried by a pivoted arm 118, operated as described in Specification 402,447. The frame 23 is lowered prior to splicing by closing a switch which serves to close a circuit to energize its operating motor and also to complete a " hold-in " circuit so that the switch may bereleasedwithout stopping this motor. Increased tension of the running web results when the brush frame is lowered and this can be done in stages by pressing a second switch which breaks the " hold-in " circuit but maintains the motor circuit closed until this second switch is released. The motor also rotates the multiple switch referred to above and is stopped with the brush frame in its fully lowered position by the opening of contacts in this multiple switch which are included in the motor circuit. The rotation of the multiple switch closes contacts in the magnetic clutch circuit which includes the rheostat and a commutator carried by the shaft 31. Just before the brush frame reaches its lower limit, further contacts in the multiple switch are closed which energize the circuit of the motor 9 and a " hold-in " circuit for the motor, which continues to rotate the reel until a projection 114, Fig. 15, carried by the reel closes a switch 130 which, as described in Specification 437,576, runs on rollers on a support 126 and is connected with the arm 118 through linkage so that the position of the switch 130 is adjusted according to the size of the roll whereby the distance between the fresh roll and the running web is always the same. When the switch 130 is closed, the circuit of the motor 9 is broken with the roll in position for pasting. The rotation of the reel has now caused the clutch members 45, 58 to engage and as the brush-frame motor rotates the rheostat arm, more current passes through the magnetic clutch which accordingly drives the fresh roll at a speed synchronous with the speed of the expiring web, the variable speed gear 101 having been automatically adjusted by means of the roller 119. With the brush frame down and the fresh roll rotating, the operator closes a further switch which energizes, through a rotating contact driven by the shaft 31 at a speed synchronous with that of the fresh roll, solenoids for operating the brush 21 and a measuring relay, and also a " hold-in " circuit for maintaining these solenoids energized. The brush 21, Fig. 20, is carried by a shaft 135, pivoted in the frame 23 and is held against the action of springs tending to press it towards the web by a latch 147 connected to the armature of the solenoid 145. When the solenoid is energized the latch moves to release the brush and the device is reset during the backward movement of the brush frame by a rod 158 and crank 160 which is provided with a clutch member adapted during the movement to engage a corresponding member on the shaft 135 whereby this is rotated to reset the brush shaft and re-engage the latch 147. The measuring relay solenoid allows the operation of a one-revolution switch which is similar to that of Specification 402,447 and effects the release of the severing knife 24, the re-starting of the brush-frame motor to raise the brush frame and the operation of the device for displacing the spoiled papers on the delivery, a signal lamp being arranged to indicate that spoiled papers are being delivered. The brush frame may also be raised by means of a special switch in the motor circuit, and during the backward rotation of the frame the knife is reset by the rotation of the shaft 135 which is operating to reset the brush 21 and the latch therefor, and which is provided with a projection 163 adapted to engage a cam 166 on the knife shaft to rotate this shaft and thus bring a cam 155 under the looking rod 154, which is connected to the armature of the knife operating solenoid. The brush-frame motor in returning the brush frame to its original position recloses contacts in the multiple switch in the circuit for the motor 9 which is set in rotation and moves the spliced roll towards the tension straps, whereupon the projection 114 opens the switch 130 and thus breaks the circuits of the solenoids operating the brush 21, the measuring relay and the " hold-in " circuit for these devices. The reel continues to rotate until a projection on the reel opens a switch fixed to the supporting frame which breaks the circuit of the motor 9 with the spliced roll in engagement with the tension straps. The brush frame rises, resetting the rheostat and breaking the circuit of the magnetic clutch, until contacts in the multiple switch are opened and break the circuit of the brush-frame motor when the brush frame is in its fully elevated position and the device is reset for the next splicing operation. A safety switch is provided in the multiple switch to prevent reverse or forward rotation of the roll frame by the motor 9 when the brush frame is not in its fully elevated position. In normal running and until the roll is nearly exhausted, the active roll is moved into contact with the tension straps but while the roll is large it is not carried into the straps far enough to have roller 71, Fig. 3, move up the incline B on cam 73 so that during this time the clutch 58, 45 is engaged and any engagement of the magnetic clutch acts as a brake. When the press is stopped by closing an emergency stop switch, contacts in the magnetic clutch circuit are also closed, whereby the clutch is energized to retard the roll. The brush 21 is formed in sections, one section for each page width of the roll, and each section is provided with its own spring for pressing the brush against the roll. One or more of these springs may be rendered inoperative if rolls of less than full width are employed by means of latches, one for each brush section, which are held in locking position by the tension straps 13, one or more of which is also rendered inoperative to correspond to the number of brush sections.